A process and system for removing tars from synthesis gas uses glycerol produced as a byproduct of biodiesel manufacture. The biodiesel may be made from various oil feedstocks such as canola, rapeseed, or soybean oils. Associated with the harvesting of these crops may be the ready availability of byproduct biomass useful as feedstock for gasification. In addition, methanol may be sourced from the gasification of biomass to exploit a potential synergy between biodiesel manufacture and biomass gasification. The present invention develops those synergies further by making use of a byproduct stream from the manufacture of biodiesel to remove tars from the gasifier synthesis gas and to provide a useful end use for the byproduct.